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  • Ok, so here is my situation.

    I am in a company that has roughly 15 Cisco APs in a warehouse using good 'ol 802.11g.

    We have roughly 26 forklifts that another company wants to add a sensory device to transmit information to a central server that we will setup.

    Everything I have learned and know, tell me this is a ZigBee, or some type of 802.15.4 standard.

    Here is the information i have received....

    Frequency band = 902-928 MHz
    Power output = 500 mW
    RF Data rate = 115.2 Kbps
    Spread Spectrum Type = FHSS
    Channel Capacity = 10 hop sequences share 50 frequencies
    Encryption = 256-bit AES

    Now for ZigBee the data rate is 40 Kbps (for the 900 MHz U.S. spectrum), not 115.2 Kbps , but in the 2.4 GHz spectrum it is capable of 250 Kbps.

    Am I on the right track as identifying this as an 802.15 device? The only other thing that is throwing me off is that 802.15 states as using DSSS not FHSS. Surely this isn't a bluetooth setup.

    When we were on the phone with the distributor of the product that we may install, I had asked him specifically what standard does their RF equipment use. His reply "Its not a standard, its just plain 900 MHz system" That was about all I could get out of him, so apparently he didn't know his own product.

    I have been assigned the task of getting concrete documentation (more than a white paper saying 900 MHz will not interfere with 2.4 GHz network) to provide our senior VPs of the distribution center as how this will all work. And if I can be sure that this is indeed some type of 802.15 wireless PAN, than I can do the rest, its just that some of the specs threw me off.

    For Details, please follow this link...
    http://www.digi.com/products/wireless/long-range-multipoint/xtend-modulespecs.jsp

    Thanks! 8)

  • Why not just use location tracking on top of your current WiFi devices ?

    Ekahau for example do this:

    http://www.ekahau.com/?id=4200

    That might suit your needs.

    Neil Mac
    CWNT

  • I am not authorized to make that decision. This is coming from the Forklift manufacturer, Raymond that is going to setup and implement this for us. It is my job to make sure it doesn't interfere with our current system along with specs.

    Raymond uses a proprietary system called iWarehouse for data tracking on the lifts ranging from maintenance schedules, to impact reports if someone hits an object.

    Has any one ever worked with these devices or know what type of standard they use?

  • Ok, so I think I may have solved my own question.

    This module uses FSK that apparently was used with early modems on standard telephone landlines.

    So its not ZigBee, nor is it 802.15, I guess its just a plain cordless phone RF signal that really doesn't have a standard per se?

    But if implemented, what kind of noise would be generated, if any, that the 802.11g system would see with 26 lifts running at 500 mW of power output.

    I don't this being an issue to our 2.4 GHz system at all, but wanted to see if any one concurred with my findings.

  • The forklift based devices in 902-928 MHz should have no impact on your 802.11g devices in 2.4GHz. There is too much seperation of frequency for that to happen.

  • BryanH Escribi?3:

    The forklift based devices in 902-928 MHz should have no impact on your 802.11g devices in 2.4GHz. There is too much seperation of frequency for that to happen.



    True, but you do want to have some distance between your AP antennas and the sensor antennas. 5 - 10 feet, as not to cause modulation issue...

    Would you not agree Bryan?

  • Yes I know that there is too much separation, but I have to provide more documentation than a white paper stating so.

    I found that this device is FCC certified under 15.247 , which is the basis of IEEE 802.15 networking. So I was partially correct to identify this system as 802.15, so that I can provide IEEE and FCC documentation to the VPs and other non-technical personnel that this will have nothing to do with our network.

    I was more or less making sure that my deductive reasoning was correct as I have taken on my first official wireless project with an enterprise corporation.

  • hammerwalk Escribi?3:

    Yes I know that there is too much separation, but I have to provide more documentation than a white paper stating so.

    I found that this device is FCC certified under 15.247 , which is the basis of IEEE 802.15 networking. So I was partially correct to identify this system as 802.15, so that I can provide IEEE and FCC documentation to the VPs and other non-technical personnel that this will have nothing to do with our network.

    I was more or less making sure that my deductive reasoning was correct as I have taken on my first official wireless project with an enterprise corporation.



    The vendor providing this solution should be able to provide you these specifications as well as the type of wireless communication. If they are Zig or perhaps a propriatary communication. I would ask for these specifics.

    I have also in the past had vendors put in writing that their said solution will not cause interference or other harm to communications as an extra step to CYA...

  • Yeah thats what we are doing now that I have the documentation, but being a 3rd Party Logistics Corp, there is a lot of red tape to go through before anything is implemented.

    It was a pain to get the information from the vendors which isn't always a good sign. But I ended up getting the FCC ID and went from there.

  • The distance between radios so far apart in frequency should not matter that much. 802.11b/g and 802.11a radios co-exist in the same access points with no problems. A radio in the 900mHz range and one in 2.4GHZ should not have problems being near each other. I would focus more on the demands of the aplications being used and the requirements of the users.

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